The present invention relates to compounds which correspond to the general formula (I) 
in which
R1, R2, R3 and R4 each represent, independently of each other, a hydrogen or halogen atom or a nitro, amino, trifluoromethyl, cyano, hydroxyl, (C1-C6)alkyl or (C1-C6)alkoxy group,
X represents
either a nitrogen atom, in which case Z represents a group of the formula Cxe2x80x94R5 or a nitrogen atom,
or a group of the formula Cxe2x80x94R6, in which case Z represents a nitrogen atom,
R5 and R6 each represent, independently of each other, a hydrogen or halogen atom or a trifluoromethyl, cyano, hydroxyl, (C1-C6)alkyl or (C1-C6)alkoxy group, and
R7 represents a hydrogen atom or a (C1-C6)alkyl group.
The compounds of the invention can exist as bases or as acid addition salts.
In accordance with the invention, it is possible to prepare the compounds of the general formula (I) by a process which is illustrated by the scheme which follows.
1,4-Diazabicyclo[3.2.2]nonane of the formula (II) is reacted with a heterocyclic compound of the general formula (III) in which R1, R2, R3, R4, R7, X and Z are as defined above and W represents a halogen atom. In this way, it is possible to perform a Buchwald-type coupling reaction (J. Org. Chem. 1997, 62, 6066-6068) in the presence of a palladium catalyst, such as palladium acetate, tris(dibenzylideneacetone)-dipalladium (0), etc., of a complexing ligand such as triphenylphosphine, tributylphosphine or 2,2xe2x80x2-bis(di-phenylphosphino)-1,1xe2x80x2-binaphthyl, and of a base, for example an organic base, such as sodium tert-butoxide, or an inorganic base, such as cesium carbonate. 
It is also possible to carry out a nucleophilic substitution reaction in the presence of a strong base such as cesium carbonate or triethylamine.
The preparation of 1,4-diazabicyclo[3.2.2]-nonane is described in J. Med. Chem. 1993, 36, 2311-2320.
The compounds of the general formula (III) are either commercially available or can be obtained by methods which are described in the literature.
The examples which follow illustrate the preparation of some compounds of the invention. The elemental microanalyses and the IR and NMR spectra confirm the structures of the compounds which are obtained. The numbers indicated in brackets in the titles of the examples correspond to those of the 1st column of the table which is presented further below. In the names of the compounds, the hyphen xe2x80x9c-xe2x80x9d is part of the word and the hyphen xe2x80x9c_xe2x80x9d is only used for the break at the end of a line; it is not to be used in the absence of any break and should not be replaced either by a normal hyphen or by a space.